US President Donald Trump and China's President Xi in Beijing on Nov. 9, 2017

President Donald Trump on Thursday unveiled a package of tariffs targeting Chinese imports in response to the country's theft of US intellectual property and technological know-how, in a move that's likely to spark retaliation from Beijing.

The US has accused China of distorting global markets by allowing its companies — including state-owned giants — to steal intellectual property from American firms, a charge Beijing denies.

In a presidential proclamation Trump confirmed he would exclude six countries — Argentina, Australia, Brazil, Canada, Mexico and South Korea — and the European Union from the tariffs, until at least May 1.

In an event ahead of the signing of the tariffs, which reportedly will target $50 billion worth of Chinese goods, Trump said that he has a "great relationship" with Chinese President Xi Jinping, but the trade imbalance between the two countries warranted the US move.

Trump gave multiple estimates of just how large that deficit is — "depending on the way you calculate, of $504 billion, some people would say it's really $375 billion, many different ways of looking at it" — but regardless of the size, he had asked China to lower the imbalance by $100 billion.

The new tariffs, however, are sure to put greater pressure on diplomatic ties, as has been seen in the aftermath of Trump's recent announcement that aluminum and steel entering the US would soon face new tariffs. Observers fear Trump's desire for individual trade deals and tariff rates outside of the World Trade Organization's structure could lead to a trade war, which economists have warned could have broad ramifications for the global economy.

Those fears were reflected on the stock market — the Dow Jones Industrial closed more than 700 points down after a slide that begun soon after the tariffs were launched.

Richard Drew / AP

"The word is reciprocal," Trump said at the White House event. "That's the word I want everyone to remember. We want reciprocal, mirror. Some people call it a mirror tariff or a mirror tax. Just use the word reciprocal. If they charge us, we charge them the same thing. That's the way it's got to be. "

The tariffs are being enacted under what's known as a Section 301 action, which grants the president the ability to correct what are seen as unfair practices among the US's trade partners. In this case, US Trade Representative Robert Lighthizer said during the signing event, the focus was on the technology sector and the protection of intellectual property rights.

Lighthizer also said that the US would also be filing a World Trade Organization complaint against China.

An official with the trade representative's office told reporters ahead of Thursday's event that US government investigators found, in the course of an investigation ordered by Trump last year, that China is using laws that curb foreign ownership of companies to force American firms to share intellectual property with Chinese business partners.

News about the coming tariffs was criticized by dozens of business associations in the US, which said they could negatively impact supply chains and drive up the prices of consumer goods for American customers. Lighthizer has said the tariffs would minimize harm to US consumers.

US criticism of Chinese intellectual property theft is not new. But since his time as a presidential candidate, Trump has vowed to take a particularly tough line on China, which he sees as taking advantage of the US with unfair economic policies that have led to the loss of American manufacturing jobs.

The Chinese Embassy in the US issued a statement Thursday afternoon calling the new tariffs "typical unilateral trade protectionist action."

"China does not want a trade war with anyone," the statement provided to BuzzFeed News continued. "But China is not afraid of and will not recoil from a trade war. China is confident and capable of facing any challenge. If a trade war were initiated by the U.S., China would fight to the end to defend its own legitimate interests with all necessary measures."

However, conclusions agreed by the 28 leaders after a European Council summit on Friday called on the US to make the exemption permanent.

The feeling among European government officials BuzzFeed News spoke to in Brussels is that by making the exemption last only a few weeks, Trump is basically trying to hold the EU to ransom.

Still, views among governments vary between those wanting a more cautious approach so to avoid the standoff escalating, and those who would prefer the EU to be more proactive in countering what in effect amounts to a threat that will continue to hang over the bloc.

Others would have liked to see the EU go beyond simply calling for a permanent exemption, and also make a larger point about condemning unilateral action.

“To some extent the council conclusions reflect caution and concern. Leaders should clarify that the main goal remains to reaffirm the exclusivity of a rules-based multilateral system,” a senior diplomat from a major European government told BuzzFeed News.

“The real issue needs to be a condemnation of unilateral action, and the reaffirmation that action should only be taken in the content of the WTO [World Trade Organisation] — and we should tell the US that we are ready to work together to improve the WTO,” the diplomat added.

Megha Rajagopalan is a world correspondent for BuzzFeed News and is based in the Middle East.